Effect of Bed Forms and Vegetated Banks on Velocity Distributions and Turbulent Flow Structure
Publication: Journal of Hydrologic Engineering
Volume 16, Issue 6
Abstract
On the basis of laboratory experiments, this paper investigates the effect of different bed forms and vegetated banks on flow velocity, Reynolds stresses, and turbulence intensities. Experimental measurements were made over fifth and sixth dunes in a series of seven of two-dimensional (2D) asymmetric gravel dunes that had lee-slope angles of 28° and 35°, respectively. These dunes had a mean wavelength of 0.96 m, mean dune height of 0.08 m, and width equal to the flume width. Rice stems with a median diameter of 2.7 mm and a stem distribution density of were used to cover the flume banks for simulating vegetation on river banks. From experimental measurements, the effect of the distance from the vegetated bank on the velocity field, turbulent intensities, and Reynolds stress distribution; the effect of different angles of lee slope of gravel dunes on the characteristics of a flow-in vegetated flume; and the reattachment points for different angles of lee slope of gravel dunes were investigated.
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Information & Authors
Information
Published In
Journal of Hydrologic Engineering
Volume 16 • Issue 6 • June 2011
Pages: 495 - 507
Copyright
© 2011 American Society of Civil Engineers.
History
Received: May 25, 2010
Accepted: Oct 8, 2010
Published online: Oct 12, 2010
Published in print: Jun 1, 2011
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